Why do objects float?
Any object dropped into a liquid displaces that liquid. A floating object weighs the same as the liquid it displaces. An object that sinks, weighs more than the liquid it displaces.
We then took a styrofoam cup filled with molassis which weighed 2 grams in total and dropped it into the water. The cup floated on the water. We asked the students to tell us how much water should pour out onto the scale. The answer was 2 grams.
By pouring more molassis into the cup you can explain to the class the loading of a freight liner.
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